This invention relates to a medical diagnostic ultrasound system and method for multiple image registration. In particular, frames of data associated with different azimuthal positions of a transducer are combined to form an panoramic field of view composite image. By registering data associated with the transducer array at various positions along the azimuthal axis, a larger compound image may be generated.
The data associated with the transducer array and the ultrasound system is collected in frames. Each frame of data represents one scan of a region. As a transducer is translated along the skin of a patient, other regions are scanned and a corresponding frame of data is stored. The region scanned for one frame of data may overlap with a region scanned for another frame of data. Therefore, each frame of data relates to another frame of data as a function of a translation in either or both of axial and azimuthal dimensions and a relative rotation.
Various algorithms for generating a panoramic field of view composite image are known. For example Weng et al., U.S. Pat. No. 5,575,286, disclose a method for estimating the translation and rotation between two or more images. A first image is divided into a plurality of subimage regions as a function of a block size. Using the arbitrarily selected sub-regions, speckle or other image data may be correlated to the second frame of data. A motion vector associated with translation in the azimuth and axial dimensions is estimated for each of the sub-regions. The relative position between the first image and a second image in terms of translation and rotation is estimated from the plurality of sub-region motion vectors.
The present invention is directed to a new system and method for registering a plurality of images as a function of relative translation and rotation.